Encore Wireless N300 PCI-E Adapter 2dbi Antenna (ENEWI-2XN42) Up to 300 Mbps Transfer Speed - Ideal for Sharing Files, Streaming Video, and Playing Online Games Detachable Antenna for Easy Upgrade GreenWLAN - Optimum Energy Efficiency with Smart Power Management Provide Wireless Speed up to 300mBps maximum PHY data rate using 40MHz bandwidth and 144.4Mbps maximum PHY data rate using 20MHz bandwidth Backward Compatible with IEEE 802.11g